From Metabolism to Reproduction: The Emerging Roles of Adipokines in Neuroendocrine Regulation, Gonadal Function, and Sexual Behavior.

Adipokines are proteins synthesized and secreted by several tissues, predominantly adipose tissue, which regulate multiple physiological functions. Historically, they have been mainly associated with regulating energy homeostasis, including glucose metabolism and body weight control. However, accumulating evidence over the past decade indicates that their actions extend far beyond metabolic processes. Adipokines are now recognized as pleiotropic hormonal mediators exerting systemic effects on various organs, including the central nervous system, where they modulate neuroendocrine circuits essential for complex physiological functions. Understanding the mechanisms that regulate reproductive function is crucial for elucidating reproductive physiology and improving fertility-related clinical outcomes. In this review, we focus on an underexplored aspect of adipokines' function: their role as modulators of reproduction and sexual behavior. Recent data demonstrate that several adipokines, including leptin and apelin-13, modulate hypothalamic-pituitary-gonadal axis function and neural circuits involved in reproductive physiology and sexual behavior. Peripheral reproductive actions, including effects on steroidogenesis and gametogenesis, are discussed as complementary mechanisms that interact with central neuroendocrine regulation. Furthermore, dysregulation of adipokine signaling pathways has been linked to various reproductive disorders and fertility impairments in both males and females. These findings underscore the importance of considering adipokines within the broader context of reproductive physiology.